Quantum annealing of pure and random Ising chains coupled to a bosonic environment

TL;DR

This paper investigates how bosonic environments affect quantum annealing in Ising chains, introducing a new numerical method to analyze systems with up to 64 spins, revealing that baths disrupt the annealing process.

Contribution

A novel numerical approach combining QUAPI and MPS to study open quantum systems during annealing, capable of handling larger spin systems.

Findings

Bosonic baths disturb quantum annealing in Ising chains

Numerical method efficiently simulates systems up to 64 spins

Bath effects are significant in both pure and random chains

Abstract

We study quantum annealing of pure and random transverse Ising chains that are coupled to boson baths, using a novel numerical method based on the combination of the quasi-adiabatic propagation path integral (QUAPI) and the matrix product state (MPS) formalisms. We present numerical results on systems up to 64 spins and conclude that the baths disturb quantum annealing of pure and random Ising chains. The numerical method to compute the reduced density matrix is described in detail.